You're GPU bottlenecked here for gaming. By how much, depends on the resolution of your monitor.

I figured I was gonna need a new graphics card, but a little verification never hurts. I usually run 1360x768 on my main monitor(26" 720p lcd tv) and 1600x900 on my auxiliary screen(acer 21" LED monitor).
Any suggestions on a PCI-E 2.0x16 card with a $150 USD budget?